Compound of cobalt cyanate with alpha tertiary base



QPatented Mar. 11, 1930 f J NITED "STATES- mm L. nnvrs,

- Ho Drawing.

I My invention relates to reaction products 'of'cobalt cyanate with a tertiary base and to methods of obtaining new chemical compounds by the reaction of cobalt cyanate with 5 a tertiary base such as pyridine or quinoline. One of the obj ects'of my invention isthe prep aration from p ridine and quinoline ,of new compounds use 111 in the preparation of temperature-ihdicating solutions.

I have discovered that when a tertiary base such as pyridine or quinoline is slowly added, preferabl with stirring, to an aqueous solution ofcohalt cy'anate, there are formed compounds not previously known or prepared,

16 and having uniqueand valuable properties. i

As an example of m present invention I will describe a method which I may employ in the preparation of cobalt pyridine cyanate in solid form. One molecular equivalent ofcobalt chloride is preferabl dissolved in water.

and the solution isinixe with a solution of two molecular equivalents of'potassiuni cyanate similarl'ydissolved'in water; The deep blue solution resulting fromthe mixing of the v solutions ofcobaltchloride andpotassium cyanate contains cobalt cyanate. To this dee blue solutionI now'slowly add pyridine, pre

I "erably with vi rous agitation. Upon the addition of pyridine, a precipitate of blue color begin's'toform, but upon further 'addi 'tion of pyridine the color of this precipitate gradually changes to pink. I prefer to continue toadd .pgrid ine until a slight excess is present, as evi enced by the pink color .of the precipitate. This pink precipitateis cobalt I pyridine cyanate, and may be obtained from the solution in solid crystalline condition by extraction with a suitablesolvent. I prefer to v employ chloroform as the solvent, preferably ,9 extracting twice withfresh portions of chloroform. The chloroformsolutionis conveniently freed from alIy droplets of water that may be present by tering through a porous medium previouslywet withchloroform. In

the preparation of small amounts of cobalt' Y pyridine cyanate, a piece of filter paper pr'e- Application filed April 16,

cobalt cyanate [which is a P A TENT, OFFICE or nonwnnrimnssacnusnrrs, nssreivon or onn mr 'ro WALTER o. :smennme, or ALLENTOWN, rmmsvnvnnm i common]: or coBAL'r camera w s A 'rm'rmmr BASE 1928. Serial in. 270,5?5.

cyanate is next allowed to evaporate, either spontaneously or by-very gentle warming, and upon the evaporation of the chloroform there is left reddish crystals of cobalt pyridine cyanate. These red crystals are stable in an atmosphere saturated with p idine, and may conveniently be kept in a esiccator or other vessel in whichsome sticks of caustic potash and a small quantity of pyridine are kept in separate containers, for thepurpose of to maintaining the atmosphere in contact with the crystals of cobalt pyridine cyanate substantially dry with respect to water but substantially satlirated with respect to pyridine: By slowly adding'quinoline to an' aqueous solution formed by the reaction of one molecular equivalent of cobalt chloridewith two molecular equivalents of potassium cyanate, in an analogous manner to that above described for the preparation of cobalt pyridine cyanate, I can obtain cobalt quinoline cyanate in aqueous solution, and by-extraction with chloroform or other suitable solvent, I can obtain solutions of cobalt quinoline cyanate substantially free from water, but cobalt quinfoline cyanate does not readily crysta lize, and I prefer to prepare and utilize cobalt quinoline cyanate in solution as indicated. {Although in describing the preparation of these new compounds of cobalt cyanate with a tertiary base I have referred to the use of cobalt chloride and potassium cyanate as my convenient manner than that above described may be utilized in the preparation of mynew,

bodies of cobalt cyanate with pyridine iand uinoline.' My present invention're lates to i t e new bodies-cobalt quinoline 'cyanate and cobalt pyridine cyanate, and to the methods 1 of their preparationin aqueoussolution and in crystalline condition and is of course in-' dependent of the means emploged to olbgain own y.

viously wet with chloroform forms a conven ,However; I find that the reaction in aqueous I ient means of separating any water present firom the chloroform solution. a

The chloroform solution of cobalt pyridine solution of one molecular equivalent of cobalt chloride (or other convenient salt of cobalt) and two molecular eguivalents'of potassium 7: pgs pyridine.

' cobalt quinoline cyanate) ap cyanate (or other convenient cyanate) forms a simple, and inexpensive method of reparing cobalt cyanate in dissolved conditlon and particularly suitable for reaction with a tertiary base such as above described. a

Cobalt pyridine cyanate is relatively insoluble in carbon tetrachloride and in carbon bisulfide, but it is readilylsolu'ble in chloro- 1 form, benzene, alcohol and acetone, and is moderately soluble in toluene and xylene. Cobalt quinoline cyanate is in eneral soluble in the same solvents which issolve cobalt pyridine cyanate. Although in these specifications I have referred to cobalt pyridine cyanate and to cobalt quinoline cyanate asthough each of these bodies were distinct and individual chemical entities, I wish to point out that the chemical behaviour of these bodies indicates the probability that each of them re resents not a single compound of definite c em ical composition, but rather a series of compounds va ing in the amount of combined hus red cobalt pyridine cyanate, or example, when exposed to an atmos here substantially free from yridine' ten s to slowly .lose pyridine, wit change of color from red to blue, but chemical analysis shows "so thatieven the blue material remaining after the loss of p idine as above indicated is still cobalt yrl 'ne' cyanate, the difference between -t e red cobalt pyridine cyanate and the blue cobalt pyridine cyanate being a mat- 86 ter oflthe amount of pyridine which is present in combined condition in the complex ,molecule. g

'As the unique and valuable properties of cobalt pyridine cyanate (and likewise of ar to be connected with this peculiar be aviour of variable combination between cobaltcyanate and a tertiary base, I wish it to be understood that b cobalt pyridine cyanate I do not wish i to be imited to either the red or to the blue variety, and that this term as herein used is to be understood as comprehending the new pyridine or quinoline as" iion product of cobalt cyanate with a tertiary ase. v

2. As a new product, a cobalt pyridine cyanate.

3. The process of preparing a compound of cobalt cyanate with a tertiary base which comprises contacting a tertiary basewith a solution of cobalt cyanate. 4. The process of preparing a compound of cobalt cyanate with pyridine which com-' prises contacting pyridine'with a solution of cobalt cyanate.

In testimony whereof, I have hereunto subscribed my name this seventh. day of April, 192s.v

- TENNEY L. DAVIS.

series of inter-related bodies of cobalt cyanate and pyridine which I have discovered,

' and that similarly by cobalt quinoline cyanate it .is intended to comprehend the new series of inter-related bodies of cobalt cyanate and quinoline which are analogous to a the cprresponding compounds of cobalt cyanate and pyridine.

Although I have described in these specifications specific embodiments of my present invention, it is to be understood that I wish T broadly claim such variations as fall withm'the recognized range of equivalents, and that my invention is not to be limited except asindicated in the appended claims. Iclaim: 1

a 1. As anew compound, a reac- 

